Herbicidal use of substituted o-phenylenediamines

ABSTRACT

HERBICIDAL USE OF SUBSTITUTED ALKYL O-PHENYLENEDIAMINES WHICH ARE PRODUCED BY REACTING A SUBSTITUTED BENZIMIDAZOLE WITH A ALKYLATING AGENT.

United States Patent "ice I Patented July 4, 1972 3,674,460 N,N-d i(sec-butyl)-4-methyl-o-phenylenediamine HERBICIDAL USE OF SUBSTITUTED N,N-dimethyl-4-propyl-o-phenylenediamine @PHENYLENEDIAMINES N,N-dimethyl-4-butyl-o-phenylenediamme Robert K. Howe, Bridgeton, Mo., assignor to N,N'-dimethyl-4-isobutyl-o-phenylenediamine Monsanto Company, St. Louis, Mo. 5 N,N-diethyl-4-pr0pyl-o-phenylenediamine N0 Dl'awingi t i -A%1 9 2,0 874,335 'N,N'-diethyl-4-isopropyl-o-phenylenediamine 11 '-d' --hl--h 1d" US. Cl. 71121 9 Claims N,N ipropyl 4 et y o p eny ene iamine N,N-dipropyl-4-tertiarybutyl-o-phenylenediamine N,N'-diisopropyl-4-propyl-o-phenylenediamine TR! N,N'-diisopropyl-4-tertiarybutyl-o-phenylenediarnine ABS CT OF THE DISCLQSURE N,N'-di(n-butyl)-4-propyl-o-phenylenediamine Herbicidal use of substituted alkyl o-phenylenediamines N,N-di(sec-butyl)-4-isopropyl-oh nylenediamine which are produced by reacting a substituted benzi- N,N',4- i( b 1) h 1 di i midazole with an alkylating g N,N-di(sec-butyl)-o-tertiarybutyl-phenylenediamine 15 EXAMPLE 11 This invention relates to the inhibition of plant growth This eXample demonstrates the post-emergent herbiutilizing N,N-dialkyl-4-alkyl-o-phenylenediamine. cidal activity of the N,N'-dialkyl-4-alkyl-o-phenylene- In accordance with this invention, it has been found iflm n f this iHVGH i II- that compounds of the following formula have valuable A good grade of p Soil is Placed in aluminum P herbicidal activity and compacted to a depth of about to /z" from the H top of each pan. A predetermined number of seeds of l each of several plant species are placed on top of the soil in the pans. The seeds are covered with a layer of -N R1 prepared soil, and the pan leveled. The seed-containing l pans are placed on a sand bench and maintained for ap- H proximately 14 days under ordinary conditions of sunlight wherein R is alkyl having at least one carbon atom and a and watering. N,N-4-trirnethyl-o-phenylenediamine in an maximum of 4 carbon atoms, and R is a primary or secacetone-water solution as indicated in Table I is applied, ondary alkyl having at least one carbon atom and a maxiafter 14 days in spray form to the plant specimens. The mum of 4 carbon atoms. treated plants are placed in a greenhouse and the effects The compounds of the present invention can be preare observed and recorded approximately 14 days therepared by conventional means, such as alkylation of the after. appropriate benzimidazole with alkyl sulfate or alkyl The post-emergent herbicidal activity index used in halide as illustrated by the following Example I. this example is based on the average percent injury of EXAMPLE I each plant species, and is defined as follows:

N,N,4-trimethyl-o-phenylenediamine was prepared ac- Numerical scale: Herblcldiil. actwlty cording to the following procedure: 0 g9 g f f l a i To a suitable vessel equipped with refluxing means, was i er E a i added 14.6 parts of 2,S-dimethylbenzimidazole, 12.6 parts I O crate f .actlvltyof dimethylsulfate, 13.8 parts of K CO and 150 parts of 3 Severe. herblcldal actwlty' dioxane. The mixture was refluxed for a period of about 4 Plant ls dead 15 hours. The resultant mixture was steam distilled yield- The observed data is set forth in the following table ing a cloudy white distillate. Sodium chloride was added wherein the botanical type is identified by an initial in to the distillate, and the mixture was extracted with ether. accordance with the following code: Ai\lorning Glory. FSugar Beets. K-Wild Buckwheat. PCocklebur. U-Velvet Leaf. B-Wild Oats G-Foxtail. L-Tomato. Q,Lambsquarter. V-Riee. C-Brome Grass. HCrab Grass. MSorghum. RSmartweed. W-Hemp Seshauia. D-Rye Grass. I-Pigweed. NCotton. SBarnyardgrass. E- Radish. J-Soybean. O-Corn. TWheat.

TABLE L-POSTEMERGENT HERBICIDAL ACTIVITY Contact Plant species Compound pZiQdiitABCDEFGHIJKLMNOPQRSTUVW N,N-trimethyl-o-phenylenediamine H? f 2;; g i B s fi-' The ether was dried over sodium sulfate, filtered and The compounds of this invention may be used alone or then distilled. The product was obtained at boiling point in combination with one or more herbicidal adjuvants 1llll3 C./2 mm., and identified by NMR as N,N,4- which can be solid or liquid extenders, carriers, diluents, trimethyl-ophenylenediamine. conditioning agents and the like to form herbicidal com- A-nalysis.Calcd. for C H N (percent): C, 17.96; H, positions. Preferred herbicidal compositions containing 9.39; N, 1865. Found (percent): C, 72.12; H, 9.49; N, the compounds of this invention can be used to the great- 18.57. est advantage to modify the growth of plant systems in Typical N,N'-diall yl-4-alkyl-o-phenylenediamines apsoil. The preferred compositions comprise certain wettable plicable for use in the present invention include: powders, aqueous suspensions, dust formulations, emulsi- NN,4 trimethylflphenylenediamine fiable oils and s olutions in solvents. In general these pre- NNZ 4 trfisopropy1 O Pheny1enediamine ferred compositions can all contaln one or more surface- N,N'-di(sec-butyl)-4-methyl-o-phenylenediamine actlve agents- N,N'-diethyl-4-rnethyl-o-phenylenediamine Surface-active agents which can be used in the herbi- N,N'-dimethyl-4-ethyl-o-phenylenediamine cidal compositions of this invention are set out, for ex- N,N-di(n-butyl)-4-ethyl-o-phenylenediamine ample in Searle U.S. Pat. 2,426,417; Todd U.S. Pat.

3 2,655,447; Jones US. Pat. 2,412,510 and Lenher U.S. Pat. 2,139,276. In general less than 15 parts by weight of the surface active agent is present per 100 parts by weight of the herbicidal composition.

'Wettable powders are water-dispersible compositions containing one or more of the compounds of this invention, an inert solid extender and one or more wetting and dispersing agents. The inert solid extenders are usually of mineral origin such as the natural clays, diatomaceous earth and synthetic minerals derived from silica and silicate. Examples of such extenders include kaolinites, attapulgite clay and synthetic magnesium silicate.

Preferred wetting agents are alkyl benzene and alkyl naphthalene sulfonates, sulfate fatty alcohols, amines or acid amides, long chain acid esters of sodium isothionatc, esters of sodium sulfosuccinate, sulfated or sulfonated fatty acid esters, petroleum sulfonates, sulfonated vegetable oils and ditertiary acetylinic glycols. Preferred dispersants are methyl cellulose, polyvinyl alcohol, sodium lignin sulfonates, polymeric alkylnaphthalene sulfonates, sodium naphthalene sulfonate, polymethylene bisnaphthalenesulfonate and sodium N-methyl-N-(long chain acid) taurates.

The wettable powders compositions of this invention usually contain from about 5 to about 95 parts of active ingredient, from about 0.25 to about 3.0 parts of wetting agent, from about 0.25 to about 7 parts of dispersant and from about 4.5 to about 94.5 parts of inert solid extender, all parts being by weight of the total composition. Where required from about 0.1 to 2.0 parts by weight of the solid inert extender can be replaced by a corrosion inhibitor or anti-foaming agent or both.

Aqueous suspensions are usually prepared by mixing together an aqueous slurry of one or more of the compounds of this invention, in the presence of dispersing agents to obtain a concentrated slurry of very finely-divided particles. The resulting concentrated aqueous suspension is characterized by its extremely small particle size, so that when diluted and sprayed coverage is very uniform.

Dusts are dense finely-divided particulate compositions which are intended for application to the soil in dry form. Dusts are characterized by their free-flowing and rapid settling properties so that they are not readily wind-borne to areas where they are of no value. Dusts contain primarily an active ingredient and a dense, free-flowing, finely-divided particulate extender. However, their performance is sometimes aided by the inclusion of a wetting agent such as those listed hereinbefore under wettable powder compositions and convenience in manufacture frequently demands the inclusion of an inert, absorptive grinding aid. Suitable classes of grinding aids are natural clays, diatomaceous earth and synthetic minerals derived from silica or silicate. Preferred grinding aids include attapulgite clay, diatomaceous silica, synthetic fine silica and synthetic calcium and magnesium silicates.

iThe inert finely-divided solid extender for the dusts can be of vegetable or mineral origin. The solid extenders are characterized by possessing relatively low surface areas and are poor in liquid absorption. Suitable inert solid extenders for herbicidal dusts include micaceous talcs, pyrophyllite, dense kaolin clays, ground calcium phosphate rock and tobacco dust. The dusts usually contain from about 0.5 to 99 parts active ingredient, 0 to 50 parts grinding aid, 0 to 3 parts wetting agent and 1 to 995 parts dense solid extender, all parts being by weight based on the total Weight of the dust.

The wettable powders described above may also be used in the preparation of dusts. While such wettable powders could be used directly in dust form, it is more advantageous to dilute them by blending with the dense dust diluent. In this manner, dispersing agents, corrosion inhibitors, and anti-foam agent may also be found as components of a dust.

Emulsifiable oils are usually solutions of active ingredient in water-immiscible solvents together with a sur factant. Suitable solvents for the active ingredient of this invention include hydrocarbons and Water-immiscible ethers, esters or ketones. Suitable surfactants are anionic, cationic and non-ionic such as alkyl aryl polyethoxy alcohols, alkyl and alkyl aryl polyether alcohols, polyethylene sorbitol or sorbitan fatty acid esters, polyethylene glycol fatty esters, fatty alkyllol amide condensates, amine salts of fatty alcohol sulfates together with long chain alcohols and oil soluble petroleum sulfonates or mixtures thereof. The emulsifiable oil compositions generally contain from about 5 to parts of one or more of the compounds of this invention, and about 1 to 10 parts surfactant and about 4 to 94 parts solvent, all parts being by weight based on the total weight of emulsifiable oil.

The herbicidal compositions of this invention can also contain other additaments, for example, fertilizers, other herbicides, pesticides and the like, used as adjuvant or in combination with any of the above-described adjuvants.

The compounds of this invention may be used in combination with known herbicides in order to provide enhanced biological effectiveness. The use of various herbicides in combination at the time of a single application or sequentially is common in practice. Herbicides which may be used in combination with the compound of this invention include but are not limited to: substituted phenoxyaliphatic acids such as 2,4 dichlorophenoxy-acetic acid; 2,4,5 trichlorophenoxyacetic acid, 2 methyl 4 chlorophenoxyacetic acid and the salts, esters and amides thereof; triazine derivatives, such as 2-chloro-4-ethylamino 6 isopropyl-amino-s-triazine; 2,4-bis(isopropylamino)- 6-methoxy-s-triazine and 2-methylmercapto-4,6- bis(isopropylamino)-s-triazine; urea derivatives such as 3 (3,4 dichlorophenyl) 1,1 dimethylurea and 3-(m trifluoromethylphenyl) 1,1 dimethylurea and 3 (3,4- dichlorophenyl) 1 methoxy 1 methylurea; pyridylium derivatives such as 1:1'-ethylene-2,2adipyridylium dihalide; acetanilides such as N-isopropylalpha-chloroacetanilide, and 2-chloro-2',6-diethyl-N-methoxymethyl acetanilide; acetamides such as N,N-diallylalpha-chloroacetamide, carbamates such as ethy1-N,N-di-n-propylthiolcarbamate, and 2.,3-dichloroallyl diisopropylthiolcarbamate; substituted uracils such as 5-bromo-3-sec-butyl-6-methyluracil, substituted anilines such as N,N-dipropylalpha, alpha, alpha,-trifluoro 2,-6 dinitro-p-toluidine; pyridazone derivatives such as 5-amino-4-chloro2-phenyl-3- (2H)-pyridazinone, and the like.

Fertilizers useful in combination with the active ingreclients include, for example ammonium nitrate, urea and superphosphate. Other useful additaments include materials in which plant organisms take root and grow such as compost, manure, humus, sand and the like.

When operating in accordance with the present invention, effective amounts of the compounds of this invention are applied to the plant in any convenient fashion. The application of liquid and particulate solid herbicidial compositions to the plant can be carried out by conventional methods, e.g., power clusters, boom and hand Sprayers and spray dusters. The compositions can also be applied from airplanes as a dust or a spray because of their effectiveness at low dosages.

The application of an effective or herbicidal amount of the compounds of this invention to the plant is essential and critical for the practice of the present invention. The exact amount of active ingredient to be employed is dependent upon such factors as the plant species and stage of development thereof, the amount of rainfall, as well as the specific compound employed. In foliar treatment for the control of plants, the active ingredients are ap plied in amounts from about 1 to about 50 or more pounds per acre. It is believed that one skilled in the art can readily determine from this specification, including examples, the application rate for any specific situation.

While the illustrative embodiments of the invention have been described hereinbefore with particularity, it will be understood that various other modifications will be apparent to and can readily be made by those skilled in the art without departing from the scope and spirit of the invention. Accordingly, it is not intended that the scope of the claims appended hereto be limited to the examples and description set forth herein but rather the claims be construed as encompassing all the features of patentable novelty which reside in the present invention including all features which would be treated as equivalents thereof by those skilled in the art to which the invention pertains.

What is claimed is:

1. A method of controlling the growth of plants which comprises contacting a plant with a herbicidally effective amount of at least one of the compounds of the formula wherein R is alkyl having at least one carbon atom with a maximum of 4 carbon atoms, wherein R is a primary or secondary alkyl having at least one carbon atom and a maximum of 4 carbon atoms.

2. A method in accordance with claim 1 wherein R is a primary alkyl selected from the group consisting of methyl, ethyl and propyl.

3. A method in accordance with claim 1 wherein said compound is N,N',4-trimethyl-o-phenylenediamine.

4. A method in accordance with claim 1 wherein said compound is N,N',4-triethyl-o-phenylenediamine.

5. A method in accordance with claim 1 wherein said compound is N,N'-dimethyl-4-ethyl-o-phenylenediamine.

6. A method in accordance with claim 1 wherein said compound is N,N'-diethyl-4-methyl-o-phenylenediamine.

7. A method in accordance with claim 1 wherein said compound is N,N'-diethyl-4-propyl-o-phenylenediamine.

8. A method in accordance with claim 1 wherein said compound is N,N'-diethyl-4-isobutyl-o-phenylenediamine.

9. A method in accordance with claim 1 wherein said compound is N,N-dibutyl-4-tertiarybutylo-phenylenediamine.

References Cited UNITED STATES PATENTS 5/1969 Soper 7l121 9/1969 Soper 7112l JAMES O. THOMAS, IR., Primary Examiner US. Cl. X.R. 

